Le vendredi 25 mai 2012 à 16:01 +0300, Uoti Urpala a écrit : > There is one significant difference though. When you read data back to > memory from swap, the kernel does not remember that it already exists on > disk; when the data is evicted from memory again, it is unnecessarily > rewritten to disk rather than just dropped. Thus, if you do multiple > read iterations through a large set of data (which does not fit in > memory) on tmpfs, each iteration does disk read AND write rather than > just read.
I don’t know enough of the kernel innards, but it sounds to me that if a previously swapped page hasn’t been modified, it should be kept on swap *and* memory as long as possible. If it does not, it sounds like a bug, but it would indeed lead to the behavior you describe for this specific usage pattern. -- .''`. Josselin Mouette : :' : `. `' `- -- To UNSUBSCRIBE, email to debian-devel-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/1337952290.14895.407.camel@pi0307572
